The public sector wants radical ideas? Then here's one: it should fundamentally change the way it uses language. It will make everyone better at their jobs, help them think smarter thoughts and make people more engaged with what they do.

Let's be clear – I don't mean the usual re-arranging of deck-chairs that lip-service to plain language promotes.

(Every year the Local Government Association publishes a list of banned words aimed at nobbling the excesses of public sector gobbledygook. Fine. We all have our annual snigger at phrases like "horizon-scoping" and wonder what exactly "coterminous stakeholder engagement" might mean, but – let's face it – if publishing the list worked, they wouldn't have to do a new one every year, would they?)

No, it's time to borrow an idea from the private sector that has been quietly re-shaping companies over the last few years: defining your organisation's "tone of voice". And, although it starts with words, it's actually much bigger than that.

In short: stop worrying about the language you don't want, define the language you do want, and promote that everywhere. Change everything from the homepage of your website to your internal memos. And focus on measuring how the change makes a difference: to customer satisfaction figures, to calls to service centres, to repeat complaint numbers, to whatever it is that's important to what you do.

The irony is that the government knows that even subtle changes in language can lead to big changes in the way that people (read: "service users") think and act. It's why Ofgem is auditing utility companies bills and price-rise notification letters to see if it can recommend any changes to the language that might help consumers be more actively involved in comparing and switching energy providers. If we're demanding it of private companies, shouldn't we expect it of our public services, too?

Here's an example: three years ago, The Writerstarted working with a Hampshire housing association called Testway Housing, part of the Aster Group. Initially, our brief was simple: people kept confusing Testway's job ads with those of the council (the similar-sounding Test Valley borough council), and this was causing the firm a few recruitment issues. Testway realised that if it changed the language of its ads so they sounded noticeably different from the council's, then people would not only be able to tell them apart, but they'd also get a much better sense that Testway thought differently, too. It worked.

But Testway didn't stop there: it then went on to ask everyone in the organisation to write in the new (human, friendly, jargon-free) style. Customer satisfaction ratings went up. Last year, its Investors in People audit even commented how the new way of writing had been a "major factor" in a positive cultural change within the organisation. The managing director reckons it helps their people "think more clearly".

Changing how people write won't break stretched budgets and is practical (email and BlackBerrys mean most people write at work more than ever before) and yet, because it's intrinsically linked to how we think, the effects can be disproportionately radical. Obviously, it's not going to be a panacea for over-stretched services or over-stressed frontline staff. But for services that are starting to look at how they can do things differently, paying attention to language can help people – both outside and inside – really feel that things have changed.

Nick Parker is the creative director of business language consultancy The Writer

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